"To Hear Your Banjo Play", film short, 1947 with Pete Seeger, Woody Guthrie, Sonny Terry, Margot Mayo's American Square Dance Group and others. Written by Alan Lomax and narrated by Pete Seeger.
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Cf. Cantwell, Robert, When We Were Good (1996), Harvard University Press, pp. 110, 253.
Szwed, John, Alan Lomax: The Man who Recorded Music, Penguin, 2010. Cf. p.144: "Margot Mayo was a Texan who pioneered folk music in New York and spearheaded the revival of folk dancing and square dancing there in the 1940s"